No document history when editing if encryption is enabled

[nodens]

Hi,

when encryption is enabled in owncloud (using Master Key), editing a document works but there is no history: The last revision is always overwritten by onlyoffice (be it a result from an upload or edits in onlyoffice).

So I get new versions of the file if I upload new versions directly on owncloud, but if it's edited with onlyoffice, the last revision is replaced when it's saved.

It works as intended when disabling encryption.

Is this expected behaviour? I didn't find any statement on such a limitation when encryption is enabled, be it in the onlyoffice or owncloud doc.

I could reproduce it on a proof of concept install, but since I was using the same configuration (I was testing an upgrade), it could be a configuration issue: if so I'd welcome pointers.

If this is a known issue, or if it is by design, it would be nice to have it documented somewhere ;)

Thanks!

Owncloud version: 10.11.0.6
Encryption method: Master Key
OnlyOffice Document server version: 7.2.2-56 Community Edition (using Debian packages)
OnlyOffice Owncloud connector: v7.6.7 (installed from owncloud App Market)

System: Debian 11 - php7.4 (from sury.org repo).

[nodens]

In case anyone with the issue is passing by, I also made a post on onlyoffice forums, where it was aknowledged:
https://forum.onlyoffice.com/t/owncloud-connector-no-document-history-when-editing-if-encryption-is-enabled/3821

We were not aware of this issue, thank you for detecting it. We are currently analyzing it and I will inform you about the results. Sorry for this inconvenience.